A number of optical switch technologies are currently used for controlling the passage of light through fiber optics. With one technology, electric current is applied to a polymer to create a thermal effect that changes the refractive index of a polymer. As the refractive index changes, a light beam passing through the polymer is selectively routed from an input to an output. Another optical switch is micro-machined in silicon and uses a thermally activated actuator to mechanically move a single send optical fiber relative to two receive optical fibers.
Still another micro-machined optical switch uses a cantilevered micro-machined mirror that is electrostatically positioned between a stopped and unstopped position. While this mirror may deflect light between two optical fibers, as with the aforementioned switch designs, it also is capable of optical alignment in only one dimension.
More recently, an optical switch (disclosed in commonly assigned U.S. Application Ser. No. 60/059,456 and which is incorporated herein by reference) was designed that uses an actuator assembly to transfer a light signal from an input port to an output port selected from a number of N options. Alternatively, the optical switch routes a reflected laser beam from a particular one of the N output ports towards the input port. In this assembly, the optical switch includes an actuator assembly and an imaging assembly. The laser source transmits the outgoing laser beam towards the actuator assembly. The outgoing laser beam is displaced by a rotational movement of the actuator assembly about one or two axes so as to be incident onto approximately the same location of a front surface of the imaging assembly and with a particular angular orientation relative to a central optical axis. The imaging assembly is coupled to an optical fiber bundle assembly that comprises a housing and a set of optical fibers. The optical fibers each comprise an outer sheathing which contains radial markers. The fibers are arranged as a closely packed hexagonal structure (as viewed in a cross-section in FIG. 5). The proximal ends of the optical fibers and the front face of the housing are subsequently polished as a unit to provide a planar surface for later coupling of the optical fiber bundle assembly to the back surface of the imaging assembly. The polarization axes of all the optical fibers are aligned relative to one another. The set of optical fibers comprises a set of single mode polarization maintaining (SMPM) optical fibers to carry the light signal. What is needed for optical switch manufacture is a mass production method that aligns the polarization axes of all the optical fibers in a switch relative to each other.